#include <iostream>
#include <vector>
using namespace std;
#include <algorithm>
using pii = pair<int, int>;
using ll = long long;
using i128 = __uint128_t;

using ull = unsigned long long;

struct point {
    int x, y;
};

struct edge {
    point p, q;
    point add() const {
        if (p.x == q.x)
            return {p.x, p.y + 1};
        else
            return {p.x + 1, p.y};
    }
};

bool in(const point& a, const edge& b) {
    if (b.p.x == b.q.x)
        return b.p.y < a.y && a.y < b.q.y && a.x == b.q.x;
    else
        return b.p.x < a.x && a.x < b.q.x && a.y == b.q.y;
}

point inter(const edge& H, const edge& S) {
    edge h = H, s = S;
    if (s.p.x == s.q.x) swap(h, s);
    point ans = {h.p.x, s.q.y};
    if (!in(ans, H) || !in(ans, S)) return {-1, -1};
    return ans;
};
const int N = 205;
int n1;
int n2, vst[N];
vector<int> g[N];
vector<point> peidui;
int f[N], b[N];
bool find(int x) {
    for (int y : g[x])
        if (!b[y]) {
            b[y] = 1;
            if (!f[y] || find(f[y])) return f[y] = x, 1;
        }
    return 0;
}
void solve2() {
    peidui.clear();
    int ans = 0;
    for (int i = 1; i <= n1; ++i) vst[i] = 0;
    for (int i = 1; i <= n2; ++i) f[i] = 0;
    for (int i = 1; i <= n1; ++i) {
        for (int j = 1; j <= n2; ++j) b[j] = 0;
        if (find(i)) ++ans;
    }
    // cout<<n1+n2-ans<<"\n";
    for (int i = 1; i <= n2; ++i) peidui.push_back({f[i], i}), vst[f[i]] = 1;
    for (int i = 1; i <= n1; ++i)
        if (!vst[i]) peidui.push_back({i, 0});
}
void solve() {
    peidui.clear();
    vector<point> ans;

    int n;
    cin >> n;
    vector<point> a(n);
    for (int i = 0; i < n; ++i) cin >> a[i].x >> a[i].y;
    int m;
    cin >> m;
    vector<point> b(m);
    for (int i = 0; i < m; ++i) cin >> b[i].x >> b[i].y;

    vector<edge> heng;
    vector<edge> shu;
    heng.reserve(n + 1);
    shu.reserve(n + 1);

    sort(a.begin(), a.end(), [&](const point& a, const point& b) {
        if (a.x != b.x) return a.x < b.x;
        return a.y < b.y;
    });
    for (int i = 1; i < n; ++i) {
        if (a[i - 1].x != a[i].x) continue;
        if (a[i - 1].y + 1 == a[i].y) {
            cout << -1 << '\n';
            return;
        }
        bool ok = 1;
        edge tmp = {a[i - 1], a[i]};
        for (const auto& p : b) {
            if (in(p, tmp)) {
                ok = 0;
                break;
            }
        }
        if (ok) shu.push_back(tmp);
    }

    sort(a.begin(), a.end(), [&](const point& a, const point& b) {
        if (a.y != b.y) return a.y < b.y;
        return a.x < b.x;
    });
    for (int i = 1; i < n; ++i) {
        if (a[i - 1].y != a[i].y) continue;
        if (a[i - 1].x + 1 == a[i].x) {
            cout << -1 << '\n';
            return;
        }
        bool ok = 1;
        edge tmp = {a[i - 1], a[i]};
        for (const auto& p : b) {
            if (in(p, tmp)) {
                ok = 0;
                break;
            }
        }
        if (ok) heng.push_back(tmp);
    }
    n1 = heng.size();
    n2 = shu.size();
    vector<int> vis(n2);
    for (int i = 0; i < N; ++i) g[i].clear();
    for (int i = 1; i <= n1; ++i) {
        int f = 0;
        for (int j = 1; j <= n2; ++j) {
            if (inter(heng[i - 1], shu[j - 1]).x == -1) continue;
            f = 1;
            g[i].push_back(j);
            vis[j] = 1;
        }
        // if (f == 0) {
        //     ans.push_back(heng[i - 1].add());
        // }
    }
    solve2();
    for (const auto [x, y] : peidui) {
        if (x == 0)
            ans.push_back(shu[y - 1].add());
        else if (y == 0)
            ans.push_back(heng[x - 1].add());
        else
            ans.push_back(inter(heng[x - 1], shu[y - 1]));
    }
    cout << ans.size() << '\n';
    for (const auto [x, y] : ans) {
        cout << x << " " << y << '\n';
    }
    return;
}

int main() {
    cin.tie(0), cout.tie(0), ios::sync_with_stdio(0);

    int t;
    cin >> t;
    // cout << '\n';
    while (t--) solve();
}

/*
4
7
1 3
6 6
4 7
2 1
6 3
4 1
2 6
3
3 4
6 4
3 1
2
1 1
2 2
0
3
1 1
1 3
3 3
1
1 2
3
1 1
1 3
2 3
0

*/